Many hand held devices have hand grips that provide some shock absorption. Similarly, sporting equipment, such as golf clubs and bicycles, has grips that reduce the force of impact and damp vibration.
For example, US Publication No. 20110219909 discloses a handlebar with dampers underneath the hand grips. The dampers are preferably constructed of an elastomeric or rubber-type material whereas the body of the handlebar assembly is formed of a more rigid material, such as a metal, like steel or aluminum based materials, and/or carbon fiber material. It is disclosed that the dampers are formed of a more pliable and resilient material having durometer values between about A25, a durometer value comparable to a rubber band, and about A55, a durometer value comparable to a door seal. Also disclosed are supplemental or optional grip assemblies that are configured to cooperate with handlebar assembly and dampers. The core of the grip assemblies includes a window or opening that extends in a longitudinal direction along a substantial portion of core. When the core is engaged with body of handlebar assembly, the opening overlies and exposes all or a substantial portion of the hand side of the dampers underneath. This allows the vibration or oscillation damping performance of handlebar assembly to be augmented by the vibration or oscillation damping performance attributable to grip assembly. The grip has an ear that extends in a radially outward direction from core near the outboard end of the core. This is for indexing the grip with respect to the core.
In US Publication No. 20090072455 a damper is disclosed for various applications, including sporting equipment. The damping portion comprises a first tube, a second tube and a layer of resilient material configured so that the first tube is disposed about the second tube, and the layer of resilient material is positioned between the first and second tubes.
US Publication No. 20040048701 discloses a vibration absorbing grip including a grip body formed by a multi-layer material. The material preferably includes a first elastomeric layer of vibration absorbing material which is substantially free of voids therein. A second elastomeric layer which includes an aramid material therein and is disposed on the first elastomeric layer. The aramid material distributes vibration to facilitate vibration damping. A third elastomeric layer is disposed on the second elastomeric layer and is adapted to be gripped by a user.
U.S. Pat. No. 6,959,469 discloses a pliable handle for a hand held device. As in the previous mentioned patents, there is provided a core member and an outer sheath, with gel being disposed between the core member and the outer sheath. The pliable handle is designed to deform and conform to the shape of the user's hand. The applied force causes movement of the gel, the pliable handle having a “memory effect” that causes the handle to temporarily deform for a period of time to the deformed shape before the handle returns to its original shape.
Some grips are designed to provide different amounts of damping in different parts of the hand grip, by using materials of differing durometer. For example, US Publication No. 20090271951 discloses a hand grip for hand tools and the like contains a plurality of elastomeric compositions to protect the users hand during use. As proposed a plurality of gel inserts are provided with varying degrees of hardness and density to provide an improved ergonomic design while insuring the integrity of the handle. Three layers are provided with the innermost layer being the hardest with a hardness of approximately 95 on the A Durometer scale, the middle layer having an intermediate hardness of approximately 55 on the A Durometer scale and the outermost layer being the softest with a hardness of approximately of 20 on the A Durometer scale.
The shape of the hand grip can also play a role in decreasing fatigue. For example, US Publication No. 20050039565 discloses an ergonomic hand grip. The first component is an outward protrusion of the rear portion of the grip, that is positioned towards the portion of the palm that lies under the fourth and fifth (ring and pinkie) fingers. This disperses pressure over Guyon's Canal (Ulnar Canal). The second component is an outward protrusion of the front portion of the grip, which may be positioned under the index, middle, ring and pinkie fingers. The protrusions of the front and rear portions increase the diameter of the grip itself, and improve the leverage of the handgrip. An inward curve of the grip under the thumb area may optionally be provided.
US Publication No. 20090114257 discloses the use of a damping compound that is resilient and is formed in part over the handle of a walking aid. The handle is ergonomically shaped.
As disclosed in WO/2010/069070, an ergonomic hand grip provides an ergonomic shaped handle having elastomeric inserts of various densities (durometers) on the grip surface area that complement the hand during usage of an assistive mobility device, such as a crutch or walking stick.